Not that anybody asked, but here's a tagging system I've found very helpful for my library (sitting on a music server wired to my router).
Name = movement
Album = work
Artist = performer
Then I make sure the Composer and Sort Composer fields are consistent (and empty for non-classical tracks). In theory it means I've clobbered the "actual" album information -- the truly crucial fact that when I bought this here particular recording of Shostakovich's 15th Symphony on disc 25 or so years ago, it was paired with another Shostakovich work performed by another orchestra to fill out the disk. Carrying that crucial bit of knowledge forward strikes me as a bit like being unable to mention Humphrey Bogart without mentioning who Humphrey Bogart's next door neighbor was in 1942.
Then when I open the Remote app on an iPad (or my phone) I see a consistent, alphabetized list of composers; selecting one gives me an alphabetized list of the composer's works. (The only flaw is that Remote doesn't distinguish between two different recordings of the same work, so e.g. under Satie's Gnossiennes I'll have six tracks, three of them harp transcriptions and then three on piano.)
To make this work, my server can't be logged into its Apple account, since *their* metadata vomits all over *my* metadata for any track I've purchased from them, which is my central beef with the Apple music ecosystem. Even though I don't have the tracks downloaded, if I'm logged in, then songwriters for every track I've purchased appear in my Composers list, which is an awful lot of chum when you're talking about a 50-song collection of the greatest hits of George Formby. (Log out and it turns out nice again. That is probably the only George Formby joke you'll read all year.)
Because I am Astoundingly Neurotic About Libraries (abbreviated "A.N.A.L."), for the big box sets I created pseudo-album-cover JPEGs giving the name of the composer. This kept me from having to hunt down 80 different images for the 80 discs in the Big Ol' Bernstein Box or 51 for the Emerson String Quartet. I've recently reripped some of these big boxes losslessly to get ready for the HomePod, and whomped up a Python hack to copy over the metadata from my lossy rips of the same tracks to keep from hand-entering about three thousand tracks of data.
Apple has their
recommended tagging style guide, by the way, but it's trying to hit several targets at once -- iTunes local, iTunes store, streaming, and discovery, with the result that there's a lot of redundant information, since (among other things) the digital music world congealed in its present form before there was a Composer tag.
To close the loop, using the HomePod as an Airplay speaker from my music server's iTunes means that, although I can't use Siri to select my music, I've still got a nice, indexed way to get to what I want quickly. And all it took was a vast amount of metadata work.
